This bill requires the Department of Defense's Chief Information Officer and the Defense Information Systems Agency Director to brief Congress within 120 days on how the Pentagon plans to replace its legacy Joint Regional Security Stacks system. The security upgrade is part of the Defense Department's broader effort to meet a 2027 deadline for implementing "zero trust" cybersecurity practices, which verify user identity and device security continuously rather than assuming network users are trustworthy. Congress is emphasizing that any replacement system should prioritize least-privilege access and continuous security verification for all users and devices, and it wants the Pentagon to explain how it will manage the transition without disrupting military network operations. The bill also encourages military departments and commands to use standardized, certified security solutions rather than developing separate systems, though it acknowledges they may pursue custom solutions if they can manage the transition without compromising network reliability.